The man, who has not yet been identified, is understood to have struggled during his arrest at 5.15pm on Monday in Lacey Street, Widnes, Cheshire. The arrest was for alleged affray.

He was detained and restrained and taken by police van to Runcorn police station. Shortly afterwards, he became ill and paramedics were called. He was taken to Warrington general hospital by ambulance, where he was pronounced dead at 7.09pm.

Investigators from the IPCC have been sent to Widnes to begin gathering evidence and gain initial accounts from police officers. A spokesman for the IPCC said: "During the course of the arrest it is understood police deployed pepper spray."

The man, who has not yet been named, was "restrained" and taken by police van to Runcorn police station, the spokesman said. He added: "Shortly after arrival he became unwell and paramedics were called."

A postmortem is due to be carried out on Tuesday.

The man's parents have been informed and investigators will be speaking to them to explain the IPCC's role and what is known at this stage.

Cheshire police have not made any comment about the death.

It is the second time in a week that someone has died following their arrest. Last week in Cumbria, 27-year-old Dale Burns died after he was Tasered and sprayed with pepper spray at his home in Barrow. The IPCC is investigating his death and appealing for witnesses. A postmortem failed to establish a cause of death.